Address to your company contact if possible
Open with who you are, what job you are applying for, then what degree you are getting, and when you expect to graduate
Explain a little more about your background and experience. You can elaborate on a skill, activity, or class that you mention in your resume. If something might be unclear (perhaps a study abroad experience) you can explain it.
Close by thanking the reader for their time and say you hope to hear from them. You might mention when you are available
Keep it short. Use formal grammar (don’t get casual).